Modern computers often provide one or more power-saving modes. The “Advanced Configuration and Power Interface Specification”, Revision 4.0 (Jun. 16, 2009) (the “ACPI”, which is hereby incorporated by reference in its entirety), for example, applies “to all classes of computers including (but not limited to) desktop, mobile, workstation, and server machines.” (ACPI §1). The ACPI illustrates a variety of possibilities for power-saving modes. It defines four global states for an entire system, namely Mechanical Off, Soft Off, Sleeping, and Working. (ACPI §2.2) Within the Sleeping global state, five variations of sleeping states are distinguished by whether, and to what extent, system context (e.g., CPU, chip set, system cache, memory, and platform) is maintained. (ACPI §§2.4 and 7.3.4).
A legacy computer system typically handles power-saving modes through its BIOS. The APCI describes power-management that is implemented primarily and almost exclusively by the operating system.
It is now recognized that electronic devices, especially when taken in aggregate, can consume significant energy even when in standby or sleep mode. Consequently, governments and organizations advocating energy conservation are seeking tighter control of such energy use through both incentives and regulation. Such measures might specify the maximum energy consumed per unit time (watts) that a device can use in a standby/sleep mode, or specify the total amount of energy the device can use while the device is in a standby/sleep mode. For example, the United States Environmental Protection Agency sets guidelines for a TV to qualify for an ENERGY STAR rating. Qualification requires that the TV consume less than one watt of electricity while the TV is in a “standby” mode that it allows it to respond to a remote control.
A television (TV) is a device that includes a built-in tuner to select a broadcast, cable, or satellite channel for viewing, and a monitor (or “screen”), the tuner and monitor contained within a single housing. A modern TV may be controlled by a remote control device, or “remote.” Although aspects of TV operation may utilize an operating system (OS) and one or more processors contained within the housing, a TV does not provide users with direct access to the OS, either through a command line interface or through a windowing shell. A TV does not provide users with the capability to execute arbitrary software applications. Although a TV may have tangible controls in the housing and the remote—such as buttons to select channel, volume, brightness, and contrast, or to invoke a menu system, a TV does not have a full feature alphanumeric keyboard. In these respects, a TV is distinct from a computer.